The Kaddu Klock is modular by design, making expanding and development easier.

The main (required) modules are:

Display module

Core module

Power module

Other possible expansions could be

Real Time Clock (RTC) module

GPS module (for time and possibly zonal position)

Radio module (e.g. DCF77)

WiFi module

Display module

This could be any type of display. So far this has been 7 Segments (x6) LED and a 16 x 8 LED matrix, both built on solderless breadboards and driven by SN74HC595 shift registers.

The next (planned) Display module is the first to be built on a fixed circuit board and will be a 24 x 16 LED matrix built on a 90 x 70 mm prototype veroboard with 6x 788BS (1.9mm LED 8 x 8 matrix) modules, driven by 5 SN74HC595 serial shift registers; 2 controlling the rows and 3 controlling the columns.

As the Display module will probably be the largest module it will probably be the base upon which all other modules are mounted on.

The Display module will be driven by two powerlines; Vcc (5V) and GND; and by 4 datalines controlling the cascaded SN74HC595s; SER, RCLK, SRCLK and SRCLR (Texas Instruments naming style)

Core module

The Core module hosts the (main) microcontroller that controls the other modules and runs the main code.

The current Core module is an Arduino Nano sat in a development board.

Power module

Provides power from an outside power source and/or internal battery storage, including charging circuitry fir said batteries.